Add shell scripts for enterprise MCP testing without Python dependencies

- mcp_cmds.sh: Core MCP protocol operations using curl (ping, list, call tools)
- mcp_demo.sh: Intelligent agent workflows with natural language queries

Features:
- Zero Python dependencies - uses only curl, jq, and standard Unix tools
- Multiple authentication methods (env vars, JSON files, OAuth tokens)
- Enterprise-ready with proxy support and minimal dependencies
- Complete MCP protocol implementation with session management
- Intelligent tool discovery and multi-step agent workflows
- Works in restricted environments where Python packages cannot be installed

Supports issue #112 requirements for enterprise environments with firewall
restrictions and security policies that prevent external package installation.

Author: aarora79